Follow up

MURRYSVILLE, Pa. - Respironics' bold claims for its new C-Flex CPAP technology is prompting some to question the extent to which pressure reduction upon exhalation will prove to be a major boon to compliance. In a press release last month, Respironics CEO Jim Liken said he believed C-Flex has the potential to largely replace the traditional CPAP therapy product. By lowering blower pressure on exhalation - like a bi-level device though not quite as precipitously - Respironics believes patients will become significantly more compliant with their sleep therapy. In one double-blind study that sampled nine patients, Respironics found C-Flex improved compliance by 20%. The improvement is a function of a sleep patient's ability to tolerate pressure when C-Flex backs off the epap by as much as 30%. But helping patients to tolerate pressure, said ResMed's Ron Richard, is a problem a standard CPAP feature called ramp has addressed already, and quite successfully. With ramp, a patient goes to sleep at a low-pressure setting. When the patient is asleep, the machine ramps up the pressure to the prescribed setting. Richard said getting patients to sleep on CPAP is the real challenge. Afterward, pressure toleration is not really an issue. “By the time ramp is over, the patient is asleep and can't tell if they are on 5, 8, 10 centimeters or not,” said Richard. “It's like spending the night at the Ritz Carleton or the Comfort Inn. Once you fall asleep it doesn't matter where you are.” C-Flex product manager Jay Vreeland agrees ramp is an asset. At the same time, he said Respironics' research is finding C-Flex has a positive effect on sleep fragmentation. “If a patient normally gets up four times at night, with C-flex maybe they're getting up once,” said Vreeland. “If they're getting up eight times, with C-Flex, it might be three.” But, while Richard said ResMed supports any feature that benefits compliance, he isn't sold that the next best way to attack compliance is through the box. “From our experience, and from feedback we're getting from the marketpace, there is more non-compliance related to poor fitting masks and humidification than from non-tolerance to pressure,” he said. Why? Because 80-90% of the CPAP patient base is undergoing sleep therapy at less than 10 cm, where tolerance to pressure, he argues, is not all that problematic. Vreeland disputes Richard's 80-90% estimate, hence the prevalence of CPAP machines that dial up to 20 cm. Nor does he believe tolerance to pressure is an insignificant issue at 10 cm or less. Both Vreeland and Richard agree on one point about C-Flex: Studies must bear out the heady claims. They, says Vreeland, are coming. HME